Such a hinged-breech weapon is known from DE 102 35 283 C1. It has a receiver or breech housing, a barrel part arranged to be tiltable around an axis of rotation on the receiver, a front shaft removably fastened on the barrel part, and a bearing piece arranged on the rear end of the front shaft, when viewed in the firing direction of the hinged-breech weapon, for pivotable support on the receiver. For tiltable mounting of the barrel part on the receiver in this known hinged-breech weapon, inwardly protruding hinge pins are provided on the receiver, which engage in side recesses on a hook element of the barrel and stop against semicircular rear contact surfaces of the side recesses. The bearing piece arranged on the rear end of the front shaft has rear support surfaces for pivotable mounting on matching front surfaces of the receiver. Inwardly protruding pins with at least one lateral mounting surface for mounting on corresponding abutment surfaces of the hook piece are also provided on the bearing piece. By appropriate selection of the simply replaceable pins, the position of the bearing piece relative to the hook piece can be changed and, therefore, the clamping pressure between the hinge pins and the rear mounting surfaces on the hook piece, on the one hand, and the clamping pressure between the rear support surfaces on the bearing part and the corresponding mating surfaces on the receiver, on the other hand, can be adjusted and, therefore, so can the hinge connection between the receiver and the tiltable barrel part. However, the replaceable pins with lateral mounting surfaces and the corresponding abutment surfaces on the hook piece must be precisely manufactured and machined, if necessary.
A hinged-breech weapon containing a barrel hook piece arranged to be tiltable around a rotational bearing on the receiver and a removable front shaft is also known from DE 199 09 114 C1. The front shaft in the area of a rear end has a bearing shell half open to the rear, which, together with a bearing shell half, open to the front arranged on the barrel hook piece, including a hinge pin forming the rotational joint on the receiver. The barrel hook piece contains a downwardly pointing additional tab, which forms an abutment for a stop on the front shaft part. An adapter sleeve is arranged on the front shaft, which is supported on an oblique abutment surface of the tab in the assembled state of the hinged-breech weapon and ensures clamping pressure of the two bearing shell halves against the hinge pins. The hinge connection here, however, is not easily adjustable.